Jupiter

Jupiter's four largest moons were discovered by Galileo in 1610. They are easily visible through any telescope or even binoculars, appearing as tiny stars flanking Jupiter's disk.

Io — The most volcanically active body in the solar system. Orbits fastest (1.77 days) and appears closest to Jupiter.

Europa — Ice-covered ocean world, a prime candidate for extraterrestrial life. Slightly smaller than Earth's Moon.

Ganymede — The largest moon in the solar system, bigger than Mercury. Has its own magnetic field.

Callisto — The most heavily cratered body in the solar system. Orbits farthest from Jupiter (16.7 days).

Jupiter is one of the easiest planets to observe. Even at low magnification, the cloud bands and Galilean moons are visible.

Great Red Spot — A persistent anticyclonic storm visible when it transits the central meridian. Jupiter rotates in ~9h 55m, so the GRS comes into view roughly every 10 hours.

Moon Events (next 48h) — Watch for transits (moon crosses Jupiter's disk), occultations (moon passes behind Jupiter), shadow transits (moon's shadow on Jupiter), and eclipses (moon enters Jupiter's shadow).

Magnitude — The North and South Equatorial Belts (NEB/SEB) are the most prominent dark bands. Look for festoons and white ovals.

Equipment — Binoculars show the moons. A 4" telescope at 100x reveals cloud bands. 6"+ at 200x shows the GRS and fine detail.